Sure, you could use the calculator, or any one of a dozen-odd apps that allow you to tap the screen and calculate the tip in a restaurant, but why even bother? iOS and Siri can meet your needs just by talking to your iPhone–or iPad, but won’t that get meatloaf gravy all over it?

Regardless, here’s how to ask Siri the right way to calculate the tip for the super-helpful server or bartender in your life.